Conventionally, in a driving controller for a three-phase rotating machine having a three-phase winding set, a technique is known in which a harmonic component is superimposed with a fundamental component (1st order component) of an electric voltage or electric current. For example, in JP 2014-121189 A, a technique is disclosed in which, for a controller of a multi-winding motor that includes two three-phase winding sets, a voltage command is calculated by superimposing harmonic components, e.g., 5th order, 7th order, etc., with a fundamental component. The two winding sets have a phase difference of 30 degrees with each other. Accordingly, torque ripple is canceled.